The Court in January of 2010 rocked the nation when it decided Citizens United v. FEC – a case that critics described as a “threat to democracy.” The case lifted restrictions that prevented corporations and unions from using general treasury funds to engage in independent expenditures on behalf of electoral candidates, and thereby opened the spigot on significant new spending for political campaigns.

A long list of proposals followed in the wake of the decision, including proposals to further limit the already restricted right of foreign nationals to make campaign contributions to candidates for state or federal office, or to American political parties. The Court in Citizens United expressly declined to rule on the constitutionality of restrictions on foreign nationals’ electoral spending, though Justice Stevens argued in his vigorous dissent that the reasoning of Citizens United casts doubt on such speaker-based restrictions on campaign spending.

This Essay analyzes in detail whether foreign speakers, including foreign corporations, can be fenced out of campaign electoral spending, and concludes that the constitutional case against such restrictions is very powerful, if not overwhelming. It predicts that the Court nevertheless will be loath to defy Congress on this point, particularly if the government invokes a national security interest or so-called right to prevent “undue foreign influence” over American elections. Signs are that the current Court would defer to Congress and uphold restrictions on foreign national campaign expenditures, were it to address the question directly. But to do so, it would need to ignore its own first amendment logic and especially its soaring rhetoric about the sophistication of American voters and the value of robust political expression fueled by private expenditures.

Whether this constitutional point matters, however, is questionable given the rapid development of new communications technologies. Foreign nationals, like American citizens, now have multiple ways of reaching potential voters that make efforts to territorialize such influence infeasible. Consequently, the most important constitutional question on the post - Citizens United horizon may not be who can expend funds, but whether donor identity can be disclosed so that voters can better evaluate electoral messages from foreign and non-foreign sources, and whether the privacy objections to such disclosure can, or should, be overcome.